fix dns warning

Author: Neutree

lib/offchip/Ethernet/src/Dns.cpp

@@ -252,7 +252,7 @@ uint16_t DNSClient::BuildRequest(const char* aName)
 }
 
 
-uint16_t DNSClient::ProcessResponse(uint16_t aTimeout, IPAddress& aAddress)
+int16_t DNSClient::ProcessResponse(uint16_t aTimeout, IPAddress& aAddress)
 {
     uint32_t startTime = millis();
 

lib/offchip/Ethernet/src/Dns.h

@@ -32,7 +32,7 @@ class DNSClient
 
 protected:
     uint16_t BuildRequest(const char* aName);
-    uint16_t ProcessResponse(uint16_t aTimeout, IPAddress& aAddress);
+    int16_t ProcessResponse(uint16_t aTimeout, IPAddress& aAddress);
 
     IPAddress iDNSServer;
     uint16_t iRequestId;